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Android example source code file (ContentResolver.java)
The ContentResolver.java Android example source code/* * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.content; import android.accounts.Account; import android.app.ActivityThread; import android.content.pm.PackageManager.NameNotFoundException; import android.content.res.AssetFileDescriptor; import android.content.res.Resources; import android.database.ContentObserver; import android.database.Cursor; import android.database.CursorWrapper; import android.database.IContentObserver; import android.net.Uri; import android.os.Bundle; import android.os.IBinder; import android.os.ParcelFileDescriptor; import android.os.RemoteException; import android.os.ServiceManager; import android.os.SystemClock; import android.text.TextUtils; import android.util.Config; import android.util.EventLog; import android.util.Log; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.List; import java.util.Random; import java.util.ArrayList; /** * This class provides applications access to the content model. */ public abstract class ContentResolver { /** * @deprecated instead use * {@link #requestSync(android.accounts.Account, String, android.os.Bundle)} */ @Deprecated public static final String SYNC_EXTRAS_ACCOUNT = "account"; public static final String SYNC_EXTRAS_EXPEDITED = "expedited"; /** * @deprecated instead use * {@link #SYNC_EXTRAS_MANUAL} */ @Deprecated public static final String SYNC_EXTRAS_FORCE = "force"; /** * If this extra is set to true then the sync settings (like getSyncAutomatically()) * are ignored by the sync scheduler. */ public static final String SYNC_EXTRAS_IGNORE_SETTINGS = "ignore_settings"; /** * If this extra is set to true then any backoffs for the initial attempt (e.g. due to retries) * are ignored by the sync scheduler. If this request fails and gets rescheduled then the * retries will still honor the backoff. */ public static final String SYNC_EXTRAS_IGNORE_BACKOFF = "ignore_backoff"; /** * If this extra is set to true then the request will not be retried if it fails. */ public static final String SYNC_EXTRAS_DO_NOT_RETRY = "do_not_retry"; /** * Setting this extra is the equivalent of setting both {@link #SYNC_EXTRAS_IGNORE_SETTINGS} * and {@link #SYNC_EXTRAS_IGNORE_BACKOFF} */ public static final String SYNC_EXTRAS_MANUAL = "force"; public static final String SYNC_EXTRAS_UPLOAD = "upload"; public static final String SYNC_EXTRAS_OVERRIDE_TOO_MANY_DELETIONS = "deletions_override"; public static final String SYNC_EXTRAS_DISCARD_LOCAL_DELETIONS = "discard_deletions"; /** * Set by the SyncManager to request that the SyncAdapter initialize itself for * the given account/authority pair. One required initialization step is to * ensure that {@link #setIsSyncable(android.accounts.Account, String, int)} has been * called with a >= 0 value. When this flag is set the SyncAdapter does not need to * do a full sync, though it is allowed to do so. */ public static final String SYNC_EXTRAS_INITIALIZE = "initialize"; public static final String SCHEME_CONTENT = "content"; public static final String SCHEME_ANDROID_RESOURCE = "android.resource"; public static final String SCHEME_FILE = "file"; /** * This is the Android platform's base MIME type for a content: URI * containing a Cursor of a single item. Applications should use this * as the base type along with their own sub-type of their content: URIs * that represent a particular item. For example, hypothetical IMAP email * client may have a URI * <code>content://com.company.provider.imap/inbox/1 for a particular * message in the inbox, whose MIME type would be reported as * <code>CURSOR_ITEM_BASE_TYPE + "/vnd.company.imap-msg" * * <p>Compare with {@link #CURSOR_DIR_BASE_TYPE}. */ public static final String CURSOR_ITEM_BASE_TYPE = "vnd.android.cursor.item"; /** * This is the Android platform's base MIME type for a content: URI * containing a Cursor of zero or more items. Applications should use this * as the base type along with their own sub-type of their content: URIs * that represent a directory of items. For example, hypothetical IMAP email * client may have a URI * <code>content://com.company.provider.imap/inbox for all of the * messages in its inbox, whose MIME type would be reported as * <code>CURSOR_DIR_BASE_TYPE + "/vnd.company.imap-msg" * * <p>Note how the base MIME type varies between this and * {@link #CURSOR_ITEM_BASE_TYPE} depending on whether there is * one single item or multiple items in the data set, while the sub-type * remains the same because in either case the data structure contained * in the cursor is the same. */ public static final String CURSOR_DIR_BASE_TYPE = "vnd.android.cursor.dir"; /** @hide */ public static final int SYNC_ERROR_SYNC_ALREADY_IN_PROGRESS = 1; /** @hide */ public static final int SYNC_ERROR_AUTHENTICATION = 2; /** @hide */ public static final int SYNC_ERROR_IO = 3; /** @hide */ public static final int SYNC_ERROR_PARSE = 4; /** @hide */ public static final int SYNC_ERROR_CONFLICT = 5; /** @hide */ public static final int SYNC_ERROR_TOO_MANY_DELETIONS = 6; /** @hide */ public static final int SYNC_ERROR_TOO_MANY_RETRIES = 7; /** @hide */ public static final int SYNC_ERROR_INTERNAL = 8; public static final int SYNC_OBSERVER_TYPE_SETTINGS = 1<<0; public static final int SYNC_OBSERVER_TYPE_PENDING = 1<<1; public static final int SYNC_OBSERVER_TYPE_ACTIVE = 1<<2; /** @hide */ public static final int SYNC_OBSERVER_TYPE_STATUS = 1<<3; /** @hide */ public static final int SYNC_OBSERVER_TYPE_ALL = 0x7fffffff; // Always log queries which take 500ms+; shorter queries are // sampled accordingly. private static final int SLOW_THRESHOLD_MILLIS = 500; private final Random mRandom = new Random(); // guarded by itself public ContentResolver(Context context) { mContext = context; } /** @hide */ protected abstract IContentProvider acquireProvider(Context c, String name); /** @hide */ public abstract boolean releaseProvider(IContentProvider icp); /** * Return the MIME type of the given content URL. * * @param url A Uri identifying content (either a list or specific type), * using the content:// scheme. * @return A MIME type for the content, or null if the URL is invalid or the type is unknown */ public final String getType(Uri url) { IContentProvider provider = acquireProvider(url); if (provider == null) { return null; } try { return provider.getType(url); } catch (RemoteException e) { return null; } catch (java.lang.Exception e) { return null; } finally { releaseProvider(provider); } } /** * <p> * Query the given URI, returning a {@link Cursor} over the result set. * </p> * <p> * For best performance, the caller should follow these guidelines: * <ul> * <li>Provide an explicit projection, to prevent * reading data from storage that aren't going to be used.</li> * <li>Use question mark parameter markers such as 'phone=?' instead of * explicit values in the {@code selection} parameter, so that queries * that differ only by those values will be recognized as the same * for caching purposes.</li> * </ul> * </p> * * @param uri The URI, using the content:// scheme, for the content to * retrieve. * @param projection A list of which columns to return. Passing null will * return all columns, which is inefficient. * @param selection A filter declaring which rows to return, formatted as an * SQL WHERE clause (excluding the WHERE itself). Passing null will * return all rows for the given URI. * @param selectionArgs You may include ?s in selection, which will be * replaced by the values from selectionArgs, in the order that they * appear in the selection. The values will be bound as Strings. * @param sortOrder How to order the rows, formatted as an SQL ORDER BY * clause (excluding the ORDER BY itself). Passing null will use the * default sort order, which may be unordered. * @return A Cursor object, which is positioned before the first entry, or null * @see Cursor */ public final Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { IContentProvider provider = acquireProvider(uri); if (provider == null) { return null; } try { long startTime = SystemClock.uptimeMillis(); Cursor qCursor = provider.query(uri, projection, selection, selectionArgs, sortOrder); if (qCursor == null) { releaseProvider(provider); return null; } // force query execution qCursor.getCount(); long durationMillis = SystemClock.uptimeMillis() - startTime; maybeLogQueryToEventLog(durationMillis, uri, projection, selection, sortOrder); // Wrap the cursor object into CursorWrapperInner object return new CursorWrapperInner(qCursor, provider); } catch (RemoteException e) { releaseProvider(provider); return null; } catch(RuntimeException e) { releaseProvider(provider); throw e; } } /** * Open a stream on to the content associated with a content URI. If there * is no data associated with the URI, FileNotFoundException is thrown. * * <h5>Accepts the following URI schemes: * <ul> * <li>content ({@link #SCHEME_CONTENT}) * <li>android.resource ({@link #SCHEME_ANDROID_RESOURCE}) * <li>file ({@link #SCHEME_FILE}) * </ul> * * <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information * on these schemes. * * @param uri The desired URI. * @return InputStream * @throws FileNotFoundException if the provided URI could not be opened. * @see #openAssetFileDescriptor(Uri, String) */ public final InputStream openInputStream(Uri uri) throws FileNotFoundException { String scheme = uri.getScheme(); if (SCHEME_ANDROID_RESOURCE.equals(scheme)) { // Note: left here to avoid breaking compatibility. May be removed // with sufficient testing. OpenResourceIdResult r = getResourceId(uri); try { InputStream stream = r.r.openRawResource(r.id); return stream; } catch (Resources.NotFoundException ex) { throw new FileNotFoundException("Resource does not exist: " + uri); } } else if (SCHEME_FILE.equals(scheme)) { // Note: left here to avoid breaking compatibility. May be removed // with sufficient testing. return new FileInputStream(uri.getPath()); } else { AssetFileDescriptor fd = openAssetFileDescriptor(uri, "r"); try { return fd != null ? fd.createInputStream() : null; } catch (IOException e) { throw new FileNotFoundException("Unable to create stream"); } } } /** * Synonym for {@link #openOutputStream(Uri, String) * openOutputStream(uri, "w")}. * @throws FileNotFoundException if the provided URI could not be opened. */ public final OutputStream openOutputStream(Uri uri) throws FileNotFoundException { return openOutputStream(uri, "w"); } /** * Open a stream on to the content associated with a content URI. If there * is no data associated with the URI, FileNotFoundException is thrown. * * <h5>Accepts the following URI schemes: * <ul> * <li>content ({@link #SCHEME_CONTENT}) * <li>file ({@link #SCHEME_FILE}) * </ul> * * <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information * on these schemes. * * @param uri The desired URI. * @param mode May be "w", "wa", "rw", or "rwt". * @return OutputStream * @throws FileNotFoundException if the provided URI could not be opened. * @see #openAssetFileDescriptor(Uri, String) */ public final OutputStream openOutputStream(Uri uri, String mode) throws FileNotFoundException { AssetFileDescriptor fd = openAssetFileDescriptor(uri, mode); try { return fd != null ? fd.createOutputStream() : null; } catch (IOException e) { throw new FileNotFoundException("Unable to create stream"); } } /** * Open a raw file descriptor to access data under a "content:" URI. This * is like {@link #openAssetFileDescriptor(Uri, String)}, but uses the * underlying {@link ContentProvider#openFile} * ContentProvider.openFile()} method, so will <em>not work with * providers that return sub-sections of files. If at all possible, * you should use {@link #openAssetFileDescriptor(Uri, String)}. You * will receive a FileNotFoundException exception if the provider returns a * sub-section of a file. * * <h5>Accepts the following URI schemes: * <ul> * <li>content ({@link #SCHEME_CONTENT}) * <li>file ({@link #SCHEME_FILE}) * </ul> * * <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information * on these schemes. * * @param uri The desired URI to open. * @param mode The file mode to use, as per {@link ContentProvider#openFile * ContentProvider.openFile}. * @return Returns a new ParcelFileDescriptor pointing to the file. You * own this descriptor and are responsible for closing it when done. * @throws FileNotFoundException Throws FileNotFoundException of no * file exists under the URI or the mode is invalid. * @see #openAssetFileDescriptor(Uri, String) */ public final ParcelFileDescriptor openFileDescriptor(Uri uri, String mode) throws FileNotFoundException { AssetFileDescriptor afd = openAssetFileDescriptor(uri, mode); if (afd == null) { return null; } if (afd.getDeclaredLength() < 0) { // This is a full file! return afd.getParcelFileDescriptor(); } // Client can't handle a sub-section of a file, so close what // we got and bail with an exception. try { afd.close(); } catch (IOException e) { } throw new FileNotFoundException("Not a whole file"); } /** * Open a raw file descriptor to access data under a "content:" URI. This * interacts with the underlying {@link ContentProvider#openAssetFile} * ContentProvider.openAssetFile()} method of the provider associated with the * given URI, to retrieve any file stored there. * * <h5>Accepts the following URI schemes: * <ul> * <li>content ({@link #SCHEME_CONTENT}) * <li>android.resource ({@link #SCHEME_ANDROID_RESOURCE}) * <li>file ({@link #SCHEME_FILE}) * </ul> * <h5>The android.resource ({@link #SCHEME_ANDROID_RESOURCE}) Scheme * <p> * A Uri object can be used to reference a resource in an APK file. The * Uri should be one of the following formats: * <ul> * <li>* </li> * <li> android.resource://package_name/type/name * <code>package_name is your package name as listed in your AndroidManifest.xml. * For example <code>com.example.myapp * <code>type is the string form of the resource type. For example, raw
* or <code>drawable.
* <code>name is the string form of the resource name. That is, whatever the file
* name was in your res directory, without the type extension.
* The easiest way to construct this form is
* <pre>Uri uri = Uri.parse("android.resource://com.example.myapp/raw/my_resource");
* </li>
* </ul>
*
* @param uri The desired URI to open.
* @param mode The file mode to use, as per {@link ContentProvider#openAssetFile
* ContentProvider.openAssetFile}.
* @return Returns a new ParcelFileDescriptor pointing to the file. You
* own this descriptor and are responsible for closing it when done.
* @throws FileNotFoundException Throws FileNotFoundException of no
* file exists under the URI or the mode is invalid.
*/
public final AssetFileDescriptor openAssetFileDescriptor(Uri uri,
String mode) throws FileNotFoundException {
String scheme = uri.getScheme();
if (SCHEME_ANDROID_RESOURCE.equals(scheme)) {
if (!"r".equals(mode)) {
throw new FileNotFoundException("Can't write resources: " + uri);
}
OpenResourceIdResult r = getResourceId(uri);
try {
return r.r.openRawResourceFd(r.id);
} catch (Resources.NotFoundException ex) {
throw new FileNotFoundException("Resource does not exist: " + uri);
}
} else if (SCHEME_FILE.equals(scheme)) {
ParcelFileDescriptor pfd = ParcelFileDescriptor.open(
new File(uri.getPath()), modeToMode(uri, mode));
return new AssetFileDescriptor(pfd, 0, -1);
} else {
IContentProvider provider = acquireProvider(uri);
if (provider == null) {
throw new FileNotFoundException("No content provider: " + uri);
}
try {
AssetFileDescriptor fd = provider.openAssetFile(uri, mode);
if(fd == null) {
releaseProvider(provider);
return null;
}
ParcelFileDescriptor pfd = new ParcelFileDescriptorInner(
fd.getParcelFileDescriptor(), provider);
return new AssetFileDescriptor(pfd, fd.getStartOffset(),
fd.getDeclaredLength());
} catch (RemoteException e) {
releaseProvider(provider);
throw new FileNotFoundException("Dead content provider: " + uri);
} catch (FileNotFoundException e) {
releaseProvider(provider);
throw e;
} catch (RuntimeException e) {
releaseProvider(provider);
throw e;
}
}
}
/**
* A resource identified by the {@link Resources} that contains it, and a resource id.
*
* @hide
*/
public class OpenResourceIdResult {
public Resources r;
public int id;
}
/**
* Resolves an android.resource URI to a {@link Resources} and a resource id.
*
* @hide
*/
public OpenResourceIdResult getResourceId(Uri uri) throws FileNotFoundException {
String authority = uri.getAuthority();
Resources r;
if (TextUtils.isEmpty(authority)) {
throw new FileNotFoundException("No authority: " + uri);
} else {
try {
r = mContext.getPackageManager().getResourcesForApplication(authority);
} catch (NameNotFoundException ex) {
throw new FileNotFoundException("No package found for authority: " + uri);
}
}
List<String> path = uri.getPathSegments();
if (path == null) {
throw new FileNotFoundException("No path: " + uri);
}
int len = path.size();
int id;
if (len == 1) {
try {
id = Integer.parseInt(path.get(0));
} catch (NumberFormatException e) {
throw new FileNotFoundException("Single path segment is not a resource ID: " + uri);
}
} else if (len == 2) {
id = r.getIdentifier(path.get(1), path.get(0), authority);
} else {
throw new FileNotFoundException("More than two path segments: " + uri);
}
if (id == 0) {
throw new FileNotFoundException("No resource found for: " + uri);
}
OpenResourceIdResult res = new OpenResourceIdResult();
res.r = r;
res.id = id;
return res;
}
/** @hide */
static public int modeToMode(Uri uri, String mode) throws FileNotFoundException {
int modeBits;
if ("r".equals(mode)) {
modeBits = ParcelFileDescriptor.MODE_READ_ONLY;
} else if ("w".equals(mode) || "wt".equals(mode)) {
modeBits = ParcelFileDescriptor.MODE_WRITE_ONLY
| ParcelFileDescriptor.MODE_CREATE
| ParcelFileDescriptor.MODE_TRUNCATE;
} else if ("wa".equals(mode)) {
modeBits = ParcelFileDescriptor.MODE_WRITE_ONLY
| ParcelFileDescriptor.MODE_CREATE
| ParcelFileDescriptor.MODE_APPEND;
} else if ("rw".equals(mode)) {
modeBits = ParcelFileDescriptor.MODE_READ_WRITE
| ParcelFileDescriptor.MODE_CREATE;
} else if ("rwt".equals(mode)) {
modeBits = ParcelFileDescriptor.MODE_READ_WRITE
| ParcelFileDescriptor.MODE_CREATE
| ParcelFileDescriptor.MODE_TRUNCATE;
} else {
throw new FileNotFoundException("Bad mode for " + uri + ": "
+ mode);
}
return modeBits;
}
/**
* Inserts a row into a table at the given URL.
*
* If the content provider supports transactions the insertion will be atomic.
*
* @param url The URL of the table to insert into.
* @param values The initial values for the newly inserted row. The key is the column name for
* the field. Passing an empty ContentValues will create an empty row.
* @return the URL of the newly created row.
*/
public final Uri insert(Uri url, ContentValues values)
{
IContentProvider provider = acquireProvider(url);
if (provider == null) {
throw new IllegalArgumentException("Unknown URL " + url);
}
try {
long startTime = SystemClock.uptimeMillis();
Uri createdRow = provider.insert(url, values);
long durationMillis = SystemClock.uptimeMillis() - startTime;
maybeLogUpdateToEventLog(durationMillis, url, "insert", null /* where */);
return createdRow;
} catch (RemoteException e) {
return null;
} finally {
releaseProvider(provider);
}
}
/**
* Applies each of the {@link ContentProviderOperation} objects and returns an array
* of their results. Passes through OperationApplicationException, which may be thrown
* by the call to {@link ContentProviderOperation#apply}.
* If all the applications succeed then a {@link ContentProviderResult} array with the
* same number of elements as the operations will be returned. It is implementation-specific
* how many, if any, operations will have been successfully applied if a call to
* apply results in a {@link OperationApplicationException}.
* @param authority the authority of the ContentProvider to which this batch should be applied
* @param operations the operations to apply
* @return the results of the applications
* @throws OperationApplicationException thrown if an application fails.
* See {@link ContentProviderOperation#apply} for more information.
* @throws RemoteException thrown if a RemoteException is encountered while attempting
* to communicate with a remote provider.
*/
public ContentProviderResult[] applyBatch(String authority,
ArrayList<ContentProviderOperation> operations)
throws RemoteException, OperationApplicationException {
ContentProviderClient provider = acquireContentProviderClient(authority);
if (provider == null) {
throw new IllegalArgumentException("Unknown authority " + authority);
}
try {
return provider.applyBatch(operations);
} finally {
provider.release();
}
}
/**
* Inserts multiple rows into a table at the given URL.
*
* This function make no guarantees about the atomicity of the insertions.
*
* @param url The URL of the table to insert into.
* @param values The initial values for the newly inserted rows. The key is the column name for
* the field. Passing null will create an empty row.
* @return the number of newly created rows.
*/
public final int bulkInsert(Uri url, ContentValues[] values)
{
IContentProvider provider = acquireProvider(url);
if (provider == null) {
throw new IllegalArgumentException("Unknown URL " + url);
}
try {
long startTime = SystemClock.uptimeMillis();
int rowsCreated = provider.bulkInsert(url, values);
long durationMillis = SystemClock.uptimeMillis() - startTime;
maybeLogUpdateToEventLog(durationMillis, url, "bulkinsert", null /* where */);
return rowsCreated;
} catch (RemoteException e) {
return 0;
} finally {
releaseProvider(provider);
}
}
/**
* Deletes row(s) specified by a content URI.
*
* If the content provider supports transactions, the deletion will be atomic.
*
* @param url The URL of the row to delete.
* @param where A filter to apply to rows before deleting, formatted as an SQL WHERE clause
(excluding the WHERE itself).
* @return The number of rows deleted.
*/
public final int delete(Uri url, String where, String[] selectionArgs)
{
IContentProvider provider = acquireProvider(url);
if (provider == null) {
throw new IllegalArgumentException("Unknown URL " + url);
}
try {
long startTime = SystemClock.uptimeMillis();
int rowsDeleted = provider.delete(url, where, selectionArgs);
long durationMillis = SystemClock.uptimeMillis() - startTime;
maybeLogUpdateToEventLog(durationMillis, url, "delete", where);
return rowsDeleted;
} catch (RemoteException e) {
return -1;
} finally {
releaseProvider(provider);
}
}
/**
* Update row(s) in a content URI.
*
* If the content provider supports transactions the update will be atomic.
*
* @param uri The URI to modify.
* @param values The new field values. The key is the column name for the field.
A null value will remove an existing field value.
* @param where A filter to apply to rows before updating, formatted as an SQL WHERE clause
(excluding the WHERE itself).
* @return The number of rows updated.
* @throws NullPointerException if uri or values are null
*/
public final int update(Uri uri, ContentValues values, String where,
String[] selectionArgs) {
IContentProvider provider = acquireProvider(uri);
if (provider == null) {
throw new IllegalArgumentException("Unknown URI " + uri);
}
try {
long startTime = SystemClock.uptimeMillis();
int rowsUpdated = provider.update(uri, values, where, selectionArgs);
long durationMillis = SystemClock.uptimeMillis() - startTime;
maybeLogUpdateToEventLog(durationMillis, uri, "update", where);
return rowsUpdated;
} catch (RemoteException e) {
return -1;
} finally {
releaseProvider(provider);
}
}
/**
* Returns the content provider for the given content URI..
*
* @param uri The URI to a content provider
* @return The ContentProvider for the given URI, or null if no content provider is found.
* @hide
*/
public final IContentProvider acquireProvider(Uri uri)
{
if (!SCHEME_CONTENT.equals(uri.getScheme())) {
return null;
}
String auth = uri.getAuthority();
if (auth != null) {
return acquireProvider(mContext, uri.getAuthority());
}
return null;
}
/**
* @hide
*/
public final IContentProvider acquireProvider(String name) {
if (name == null) {
return null;
}
return acquireProvider(mContext, name);
}
/**
* Returns a {@link ContentProviderClient} that is associated with the {@link ContentProvider}
* that services the content at uri, starting the provider if necessary. Returns
* null if there is no provider associated wih the uri. The caller must indicate that they are
* done with the provider by calling {@link ContentProviderClient#release} which will allow
* the system to release the provider it it determines that there is no other reason for
* keeping it active.
* @param uri specifies which provider should be acquired
* @return a {@link ContentProviderClient} that is associated with the {@link ContentProvider}
* that services the content at uri or null if there isn't one.
*/
public final ContentProviderClient acquireContentProviderClient(Uri uri) {
IContentProvider provider = acquireProvider(uri);
if (provider != null) {
return new ContentProviderClient(this, provider);
}
return null;
}
/**
* Returns a {@link ContentProviderClient} that is associated with the {@link ContentProvider}
* with the authority of name, starting the provider if necessary. Returns
* null if there is no provider associated wih the uri. The caller must indicate that they are
* done with the provider by calling {@link ContentProviderClient#release} which will allow
* the system to release the provider it it determines that there is no other reason for
* keeping it active.
* @param name specifies which provider should be acquired
* @return a {@link ContentProviderClient} that is associated with the {@link ContentProvider}
* with the authority of name or null if there isn't one.
*/
public final ContentProviderClient acquireContentProviderClient(String name) {
IContentProvider provider = acquireProvider(name);
if (provider != null) {
return new ContentProviderClient(this, provider);
}
return null;
}
/**
* Register an observer class that gets callbacks when data identified by a
* given content URI changes.
*
* @param uri The URI to watch for changes. This can be a specific row URI, or a base URI
* for a whole class of content.
* @param notifyForDescendents If <code>true changes to URIs beginning with uri
* will also cause notifications to be sent. If <code>false only changes to the exact URI
* specified by <em>uri will cause notifications to be sent. If true, than any URI values
* at or below the specified URI will also trigger a match.
* @param observer The object that receives callbacks when changes occur.
* @see #unregisterContentObserver
*/
public final void registerContentObserver(Uri uri, boolean notifyForDescendents,
ContentObserver observer)
{
try {
getContentService().registerContentObserver(uri, notifyForDescendents,
observer.getContentObserver());
} catch (RemoteException e) {
}
}
/**
* Unregisters a change observer.
*
* @param observer The previously registered observer that is no longer needed.
* @see #registerContentObserver
*/
public final void unregisterContentObserver(ContentObserver observer) {
try {
IContentObserver contentObserver = observer.releaseContentObserver();
if (contentObserver != null) {
getContentService().unregisterContentObserver(
contentObserver);
}
} catch (RemoteException e) {
}
}
/**
* Notify registered observers that a row was updated.
* To register, call {@link #registerContentObserver(android.net.Uri , boolean, android.database.ContentObserver) registerContentObserver()}.
* By default, CursorAdapter objects will get this notification.
*
* @param uri
* @param observer The observer that originated the change, may be <code>null
*/
public void notifyChange(Uri uri, ContentObserver observer) {
notifyChange(uri, observer, true /* sync to network */);
}
/**
* Notify registered observers that a row was updated.
* To register, call {@link #registerContentObserver(android.net.Uri , boolean, android.database.ContentObserver) registerContentObserver()}.
* By default, CursorAdapter objects will get this notification.
*
* @param uri
* @param observer The observer that originated the change, may be <code>null
* @param syncToNetwork If true, attempt to sync the change to the network.
*/
public void notifyChange(Uri uri, ContentObserver observer, boolean syncToNetwork) {
try {
getContentService().notifyChange(
uri, observer == null ? null : observer.getContentObserver(),
observer != null && observer.deliverSelfNotifications(), syncToNetwork);
} catch (RemoteException e) {
}
}
/**
* Start an asynchronous sync operation. If you want to monitor the progress
* of the sync you may register a SyncObserver. Only values of the following
* types may be used in the extras bundle:
* <ul>
* <li>Integer
* <li>Long
* <li>Boolean
* <li>Float
* <li>Double
* <li>String
* </ul>
*
* @param uri the uri of the provider to sync or null to sync all providers.
* @param extras any extras to pass to the SyncAdapter.
* @deprecated instead use
* {@link #requestSync(android.accounts.Account, String, android.os.Bundle)}
*/
@Deprecated
public void startSync(Uri uri, Bundle extras) {
Account account = null;
if (extras != null) {
String accountName = extras.getString(SYNC_EXTRAS_ACCOUNT);
if (!TextUtils.isEmpty(accountName)) {
account = new Account(accountName, "com.google");
}
extras.remove(SYNC_EXTRAS_ACCOUNT);
}
requestSync(account, uri != null ? uri.getAuthority() : null, extras);
}
/**
* Start an asynchronous sync operation. If you want to monitor the progress
* of the sync you may register a SyncObserver. Only values of the following
* types may be used in the extras bundle:
* <ul>
* <li>Integer
* <li>Long
* <li>Boolean
* <li>Float
* <li>Double
* <li>String
* </ul>
*
* @param account which account should be synced
* @param authority which authority should be synced
* @param extras any extras to pass to the SyncAdapter.
*/
public static void requestSync(Account account, String authority, Bundle extras) {
validateSyncExtrasBundle(extras);
try {
getContentService().requestSync(account, authority, extras);
} catch (RemoteException e) {
}
}
/**
* Check that only values of the following types are in the Bundle:
* <ul>
* <li>Integer
* <li>Long
* <li>Boolean
* <li>Float
* <li>Double
* <li>String
* <li>Account
* <li>null
* </ul>
* @param extras the Bundle to check
*/
public static void validateSyncExtrasBundle(Bundle extras) {
try {
for (String key : extras.keySet()) {
Object value = extras.get(key);
if (value == null) continue;
if (value instanceof Long) continue;
if (value instanceof Integer) continue;
if (value instanceof Boolean) continue;
if (value instanceof Float) continue;
if (value instanceof Double) continue;
if (value instanceof String) continue;
if (value instanceof Account) continue;
throw new IllegalArgumentException("unexpected value type: "
+ value.getClass().getName());
}
} catch (IllegalArgumentException e) {
throw e;
} catch (RuntimeException exc) {
throw new IllegalArgumentException("error unparceling Bundle", exc);
}
}
/**
* Cancel any active or pending syncs that match the Uri. If the uri is null then
* all syncs will be canceled.
*
* @param uri the uri of the provider to sync or null to sync all providers.
* @deprecated instead use {@link #cancelSync(android.accounts.Account, String)}
*/
@Deprecated
public void cancelSync(Uri uri) {
cancelSync(null /* all accounts */, uri != null ? uri.getAuthority() : null);
}
/**
* Cancel any active or pending syncs that match account and authority. The account and
* authority can each independently be set to null, which means that syncs with any account
* or authority, respectively, will match.
*
* @param account filters the syncs that match by this account
* @param authority filters the syncs that match by this authority
*/
public static void cancelSync(Account account, String authority) {
try {
getContentService().cancelSync(account, authority);
} catch (RemoteException e) {
}
}
/**
* Get information about the SyncAdapters that are known to the system.
* @return an array of SyncAdapters that have registered with the system
*/
public static SyncAdapterType[] getSyncAdapterTypes() {
try {
return getContentService().getSyncAdapterTypes();
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Check if the provider should be synced when a network tickle is received
*
* @param account the account whose setting we are querying
* @param authority the provider whose setting we are querying
* @return true if the provider should be synced when a network tickle is received
*/
public static boolean getSyncAutomatically(Account account, String authority) {
try {
return getContentService().getSyncAutomatically(account, authority);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Set whether or not the provider is synced when it receives a network tickle.
*
* @param account the account whose setting we are querying
* @param authority the provider whose behavior is being controlled
* @param sync true if the provider should be synced when tickles are received for it
*/
public static void setSyncAutomatically(Account account, String authority, boolean sync) {
try {
getContentService().setSyncAutomatically(account, authority, sync);
} catch (RemoteException e) {
// exception ignored; if this is thrown then it means the runtime is in the midst of
// being restarted
}
}
/**
* Specifies that a sync should be requested with the specified the account, authority,
* and extras at the given frequency. If there is already another periodic sync scheduled
* with the account, authority and extras then a new periodic sync won't be added, instead
* the frequency of the previous one will be updated.
* <p>
* These periodic syncs honor the "syncAutomatically" and "masterSyncAutomatically" settings.
* Although these sync are scheduled at the specified frequency, it may take longer for it to
* actually be started if other syncs are ahead of it in the sync operation queue. This means
* that the actual start time may drift.
* <p>
* Periodic syncs are not allowed to have any of {@link #SYNC_EXTRAS_DO_NOT_RETRY},
* {@link #SYNC_EXTRAS_IGNORE_BACKOFF}, {@link #SYNC_EXTRAS_IGNORE_SETTINGS},
* {@link #SYNC_EXTRAS_INITIALIZE}, {@link #SYNC_EXTRAS_FORCE},
* {@link #SYNC_EXTRAS_EXPEDITED}, {@link #SYNC_EXTRAS_MANUAL} set to true.
* If any are supplied then an {@link IllegalArgumentException} will be thrown.
*
* @param account the account to specify in the sync
* @param authority the provider to specify in the sync request
* @param extras extra parameters to go along with the sync request
* @param pollFrequency how frequently the sync should be performed, in seconds.
* @throws IllegalArgumentException if an illegal extra was set or if any of the parameters
* are null.
*/
public static void addPeriodicSync(Account account, String authority, Bundle extras,
long pollFrequency) {
validateSyncExtrasBundle(extras);
if (account == null) {
throw new IllegalArgumentException("account must not be null");
}
if (authority == null) {
throw new IllegalArgumentException("authority must not be null");
}
if (extras.getBoolean(SYNC_EXTRAS_MANUAL, false)
|| extras.getBoolean(SYNC_EXTRAS_DO_NOT_RETRY, false)
|| extras.getBoolean(SYNC_EXTRAS_IGNORE_BACKOFF, false)
|| extras.getBoolean(SYNC_EXTRAS_IGNORE_SETTINGS, false)
|| extras.getBoolean(SYNC_EXTRAS_INITIALIZE, false)
|| extras.getBoolean(SYNC_EXTRAS_FORCE, false)
|| extras.getBoolean(SYNC_EXTRAS_EXPEDITED, false)) {
throw new IllegalArgumentException("illegal extras were set");
}
try {
getContentService().addPeriodicSync(account, authority, extras, pollFrequency);
} catch (RemoteException e) {
// exception ignored; if this is thrown then it means the runtime is in the midst of
// being restarted
}
}
/**
* Remove a periodic sync. Has no affect if account, authority and extras don't match
* an existing periodic sync.
*
* @param account the account of the periodic sync to remove
* @param authority the provider of the periodic sync to remove
* @param extras the extras of the periodic sync to remove
*/
public static void removePeriodicSync(Account account, String authority, Bundle extras) {
validateSyncExtrasBundle(extras);
if (account == null) {
throw new IllegalArgumentException("account must not be null");
}
if (authority == null) {
throw new IllegalArgumentException("authority must not be null");
}
try {
getContentService().removePeriodicSync(account, authority, extras);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Get the list of information about the periodic syncs for the given account and authority.
*
* @param account the account whose periodic syncs we are querying
* @param authority the provider whose periodic syncs we are querying
* @return a list of PeriodicSync objects. This list may be empty but will never be null.
*/
public static List<PeriodicSync> getPeriodicSyncs(Account account, String authority) {
if (account == null) {
throw new IllegalArgumentException("account must not be null");
}
if (authority == null) {
throw new IllegalArgumentException("authority must not be null");
}
try {
return getContentService().getPeriodicSyncs(account, authority);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Check if this account/provider is syncable.
* @return >0 if it is syncable, 0 if not, and <0 if the state isn't known yet.
*/
public static int getIsSyncable(Account account, String authority) {
try {
return getContentService().getIsSyncable(account, authority);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Set whether this account/provider is syncable.
* @param syncable >0 denotes syncable, 0 means not syncable, <0 means unknown
*/
public static void setIsSyncable(Account account, String authority, int syncable) {
try {
getContentService().setIsSyncable(account, authority, syncable);
} catch (RemoteException e) {
// exception ignored; if this is thrown then it means the runtime is in the midst of
// being restarted
}
}
/**
* Gets the master auto-sync setting that applies to all the providers and accounts.
* If this is false then the per-provider auto-sync setting is ignored.
*
* @return the master auto-sync setting that applies to all the providers and accounts
*/
public static boolean getMasterSyncAutomatically() {
try {
return getContentService().getMasterSyncAutomatically();
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Sets the master auto-sync setting that applies to all the providers and accounts.
* If this is false then the per-provider auto-sync setting is ignored.
*
* @param sync the master auto-sync setting that applies to all the providers and accounts
*/
public static void setMasterSyncAutomatically(boolean sync) {
try {
getContentService().setMasterSyncAutomatically(sync);
} catch (RemoteException e) {
// exception ignored; if this is thrown then it means the runtime is in the midst of
// being restarted
}
}
/**
* Returns true if there is currently a sync operation for the given
* account or authority in the pending list, or actively being processed.
* @param account the account whose setting we are querying
* @param authority the provider whose behavior is being queried
* @return true if a sync is active for the given account or authority.
*/
public static boolean isSyncActive(Account account, String authority) {
try {
return getContentService().isSyncActive(account, authority);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* If a sync is active returns the information about it, otherwise returns false.
* @return the SyncInfo for the currently active sync or null if one is not active.
*/
public static SyncInfo getCurrentSync() {
try {
return getContentService().getCurrentSync();
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Returns the status that matches the authority.
* @param account the account whose setting we are querying
* @param authority the provider whose behavior is being queried
* @return the SyncStatusInfo for the authority, or null if none exists
* @hide
*/
public static SyncStatusInfo getSyncStatus(Account account, String authority) {
try {
return getContentService().getSyncStatus(account, authority);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Return true if the pending status is true of any matching authorities.
* @param account the account whose setting we are querying
* @param authority the provider whose behavior is being queried
* @return true if there is a pending sync with the matching account and authority
*/
public static boolean isSyncPending(Account account, String authority) {
try {
return getContentService().isSyncPending(account, authority);
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Request notifications when the different aspects of the SyncManager change. The
* different items that can be requested are:
* <ul>
* <li> {@link #SYNC_OBSERVER_TYPE_PENDING}
* <li> {@link #SYNC_OBSERVER_TYPE_ACTIVE}
* <li> {@link #SYNC_OBSERVER_TYPE_SETTINGS}
* </ul>
* The caller can set one or more of the status types in the mask for any
* given listener registration.
* @param mask the status change types that will cause the callback to be invoked
* @param callback observer to be invoked when the status changes
* @return a handle that can be used to remove the listener at a later time
*/
public static Object addStatusChangeListener(int mask, final SyncStatusObserver callback) {
if (callback == null) {
throw new IllegalArgumentException("you passed in a null callback");
}
try {
ISyncStatusObserver.Stub observer = new ISyncStatusObserver.Stub() {
public void onStatusChanged(int which) throws RemoteException {
callback.onStatusChanged(which);
}
};
getContentService().addStatusChangeListener(mask, observer);
return observer;
} catch (RemoteException e) {
throw new RuntimeException("the ContentService should always be reachable", e);
}
}
/**
* Remove a previously registered status change listener.
* @param handle the handle that was returned by {@link #addStatusChangeListener}
*/
public static void removeStatusChangeListener(Object handle) {
if (handle == null) {
throw new IllegalArgumentException("you passed in a null handle");
}
try {
getContentService().removeStatusChangeListener((ISyncStatusObserver.Stub) handle);
} catch (RemoteException e) {
// exception ignored; if this is thrown then it means the runtime is in the midst of
// being restarted
}
}
/**
* Returns sampling percentage for a given duration.
*
* Always returns at least 1%.
*/
private int samplePercentForDuration(long durationMillis) {
if (durationMillis >= SLOW_THRESHOLD_MILLIS) {
return 100;
}
return (int) (100 * durationMillis / SLOW_THRESHOLD_MILLIS) + 1;
}
private void maybeLogQueryToEventLog(long durationMillis,
Uri uri, String[] projection,
String selection, String sortOrder) {
int samplePercent = samplePercentForDuration(durationMillis);
if (samplePercent < 100) {
synchronized (mRandom) {
if (mRandom.nextInt(100) >= samplePercent) {
return;
}
}
}
StringBuilder projectionBuffer = new StringBuilder(100);
if (projection != null) {
for (int i = 0; i < projection.length; ++i) {
// Note: not using a comma delimiter here, as the
// multiple arguments to EventLog.writeEvent later
// stringify with a comma delimiter, which would make
// parsing uglier later.
if (i != 0) projectionBuffer.append('/');
projectionBuffer.append(projection[i]);
}
}
// ActivityThread.currentPackageName() only returns non-null if the
// current thread is an application main thread. This parameter tells
// us whether an event loop is blocked, and if so, which app it is.
String blockingPackage = ActivityThread.currentPackageName();
EventLog.writeEvent(
EventLogTags.CONTENT_QUERY_SAMPLE,
uri.toString(),
projectionBuffer.toString(),
selection != null ? selection : "",
sortOrder != null ? sortOrder : "",
durationMillis,
blockingPackage != null ? blockingPackage : "",
samplePercent);
}
private void maybeLogUpdateToEventLog(
long durationMillis, Uri uri, String operation, String selection) {
int samplePercent = samplePercentForDuration(durationMillis);
if (samplePercent < 100) {
synchronized (mRandom) {
if (mRandom.nextInt(100) >= samplePercent) {
return;
}
}
}
String blockingPackage = ActivityThread.currentPackageName();
EventLog.writeEvent(
EventLogTags.CONTENT_UPDATE_SAMPLE,
uri.toString(),
operation,
selection != null ? selection : "",
durationMillis,
blockingPackage != null ? blockingPackage : "",
samplePercent);
}
private final class CursorWrapperInner extends CursorWrapper {
private IContentProvider mContentProvider;
public static final String TAG="CursorWrapperInner";
private boolean mCloseFlag = false;
CursorWrapperInner(Cursor cursor, IContentProvider icp) {
super(cursor);
mContentProvider = icp;
}
@Override
public void close() {
super.close();
ContentResolver.this.releaseProvider(mContentProvider);
mCloseFlag = true;
}
@Override
protected void finalize() throws Throwable {
try {
if(!mCloseFlag) {
ContentResolver.this.releaseProvider(mContentProvider);
}
} finally {
super.finalize();
}
}
}
private final class ParcelFileDescriptorInner extends ParcelFileDescriptor {
private IContentProvider mContentProvider;
public static final String TAG="ParcelFileDescriptorInner";
private boolean mReleaseProviderFlag = false;
ParcelFileDescriptorInner(ParcelFileDescriptor pfd, IContentProvider icp) {
super(pfd);
mContentProvider = icp;
}
@Override
public void close() throws IOException {
if(!mReleaseProviderFlag) {
super.close();
ContentResolver.this.releaseProvider(mContentProvider);
mReleaseProviderFlag = true;
}
}
@Override
protected void finalize() throws Throwable {
if (!mReleaseProviderFlag) {
close();
}
}
}
/** @hide */
public static final String CONTENT_SERVICE_NAME = "content";
/** @hide */
public static IContentService getContentService() {
if (sContentService != null) {
return sContentService;
}
IBinder b = ServiceManager.getService(CONTENT_SERVICE_NAME);
if (Config.LOGV) Log.v("ContentService", "default service binder = " + b);
sContentService = IContentService.Stub.asInterface(b);
if (Config.LOGV) Log.v("ContentService", "default service = " + sContentService);
return sContentService;
}
private static IContentService sContentService;
private final Context mContext;
private static final String TAG = "ContentResolver";
}
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